Various synthetic roof and wall coverings are known today, such as those formed of elongated thermoplastic panels that are nailed or screwed to a wall or roof support surface in horizontal courses or rows in partially overlapping relation to each other so as to provide a substantially water resistant, protective layer over the support surface. Such panels, which usually are identically molded, commonly are formed with a plurality of rows of simulated building elements, such as shake shingles. Since the panels are identically molded, a panel-to-panel identity can be easily noticed if the panels are not carefully installed. Because of the relatively large size of the panels, which usually have a length of 48 inches or more, they also are difficult to handle during installation. Installation problems particularly occur when installing such synthetic wall and roof coverings about a corner of the roof or sidewalls, and specifically, difficulties can be encountered in concealing the joints of panels at the corner.
In the installation of such synthetic panels about corners, it is common to use elongated corner moldings, each formed with a series of vertically arranged building elements corresponding to the building elements of the panels to be installed, which define 90° junctures with each other. Such corner moldings commonly have vertically extending mounting flanges adjacent opposite longitudinal sides with nail or screw-receiving apertures (i.e. fastener apertures) for securing the mounting flanges to respective angled support surfaces that define the corner. The abutting panels on opposite sides of the corner molding are mounted in overlying relation to the mounting flanges.
When starting a course of panels from a corner, the installer usually must hold the corner molding in one hand and the panel in the other hand, and at the same time attempt to align the building elements of the corner molding and panel and then secure the corner molding in place before mounting the panel. Because of the sizes of the corner molding and panel, this can be difficult, necessitating that the installer first preliminarily mount the corner molding, then arrange the abutting panel in its mounted position, then remove the mounting nails or screws from the corner molding, and readjust the position of the corner molding as necessary. Even then, it can be difficult to ensure proper alignment of the abutting simulated building elements of the corner molding and adjacent panel.
Similar installation problems occur in terminating a course of panels at a corner. The corner molding and the final panel of the course must either be simultaneously handled and aligned, or the corner molding preliminarily installed, the final panel preliminarily positioned in place, and then the corner molding reinstalled. Even slight skewing of the row, or misalignment of the building elements between the last panel and the corner molding, can significantly detract from the natural appearance of the wall covering. In such case, it is necessary for the installer to again remove the fastening nails or screws of the last panel and the corner molding, reposition the corner molding, and then remount the corner molding and panel. This is a tedious and time consuming procedure which can significantly impede the economic and efficient installation of the wall covering.